Stable hydride source compositions for manufacture of semiconductor devices and structures

ABSTRACT

A metal hydride derivative wherein at least one hydrogen atom is replaced by deuterium ( 2   1  H) or tritium ( 3   1  H) isotope. The metal constituent of such metal hydride may be a Group III, IV or V metal or a transition metal, e.g., antimony, aluminum, gallium, tin, or germanium. The isotopically stabilized metal hydride derivatives of the invention are useful as metal source compositions for chemical vapor deposition, assisted chemical vapor deposition (e.g., laser-assisted chemical vapor deposition, light-assisted chemical vapor deposition, plasma-assisted chemical vapor deposition and ion-assisted chemical vapor deposition), ion implantation, molecular beam epitaxy, and rapid thermal processing.

CROSS-REFERENCE TO RELATED APPLICATION

U.S. patent application Ser. No. 08/977,507, now U.S. Pat. No.6,005,127, in the names of Michael A. Todd, Thomas H. Baum and GautamBhandari for "Antimony/Lewis Base Adducts for Sb-Ion Implantation andFormation of Antimonide Films" is being co-filed herewith on Nov. 24,1997.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the stabilization of hydrides and othercompositions in which deuterium and/or tritium may be substituted toderivatize the hydride composition and produce a highly stabilizeddeutero- and/or tritiato-species. In a particular aspect, the inventionrelates to reagents useful as metal source compositions for ionimplantation, chemical vapor deposition, laser or light-induceddeposition, plasma-induced or ion beam-induced deposition, or othermetal formation processes, in which the metal source compositions havebeen stabilized by the incorporation of deuterium and/or tritiumsubstituents therein.

2. Description of the Related Art

In the fabrication of advanced semiconductor devices, processes such asIII-V MOCVD and p/n doping by ion implantation ideally require the useof Group III and Group V hydrides.

However, the hydrides of the heavier elements of Group III and Group Vare unstable or in some cases are simply not known. For instance,stibine is only stable at very low temperatures (-78° C.), decomposingspontaneously at room temperature, while indane cannot be isolated.

In addition, alkyl or aryl metal hydrides such as HSbR₂ and H₂ SbR,wherein R is alkyl, are also unstable.

Although literature reports indicate that researchers have synthesizedand used metal hydrides as precursors when stored at low temperatures,widespread commercialization has not been possible due to the limitedstability of the hydrides to light, heat and metal surfaces (i.e.,stainless steel).

Sophisticated microelectronic components and device heterostructures aredriving the development of CVD precursors that exhibit useful volatilityand the ability to deposit high-purity films. Currently, many III-Vdevices based upon strained layer superlattices and multiple quantumwells (MQW) are fabricated by molecular beam epitaxy (MBE). MBE isrelatively slow and expensive when compared to alternate thin-filmgrowth techniques used for microelectronics.

Although chemical vapor deposition (CVD) offers a low-cost, highthroughput approach to device manufacturing, a lack of suitable, lowtemperature CVD precursors has hindered its widespread applicability.This is particularly true for Sb-based heterostructures that displayimportant optoelectronic and electronic properties, including InSb,InGaSb, InAsSb, GaAlSb and InSbBi. Volatile and thermally stable Sbprecursors would facilitate the chemical vapor deposition of antimonidethin-films, as required for the large scale, controlled production ofantimonide based lasers, detectors and microelectronic sensors.

Antimonide materials are attractive for commercial infraredoptoelectronic applications. The compositional variety and stoichiometryof III-V compound semiconductors allows for nearly complete coverage ofthe infrared spectrum. Bandgaps ranging from 2.5 eV in AlP to 0.2 eV inInSb can be achieved by forming strained thin-films with the properelemental and stoichiometric compositions. Materials of greatestinterest include InSbBi and Inas-SbBi₈ for long wavelength (8-12 mm)infrared detectors, InAsSb and InGaSb1° for mid-infrared absorbers inmilitary applications, and InSb/In_(1-x) Al_(x) Sb₁₁ light emittingdiodes (LEDs) for mid-infrared chemical sensor applications. Many ofthese materials, however, as mentioned above are metastable compositionsthat necessitate high-purity films and low processing temperatures.

Antimonides are also of great interest as semiconductor infrared lasers.For instance, a type-II quantum well superlattice laser, comprised ofInAsSb active layer with alternating InPSb and AlAsSb cladding layers,provides 3.5 mm emission upon electron injection. Similarly,mid-infrared lasers comprised of InAs/InGaSb/InAs active regions withlattice-matching to AlSb cladding layers were also demonstrated. Thedevice fabrication requires thin-film processing of elemental aluminum,antimony, gallium and indium to produce both the active and claddinglayers, and thereby, presents a significant technological challenge. Theinherent physical properties of Ga, Sb and In necessitate low processingtemperatures to alleviate inter-diffusion, melting, and re-evaporation(i.e., InSb melts at 525° C.). Unfortunately, current Sb CVD sources,such as trimethyl antimony, require processing temperatures in excess of460° C. to achieve precursor decomposition and useful film growth rates.

SUMMARY OF THE INVENTION

The present invention relates to the substitution of deuterium and/ortritium atoms in place of hydrogen atoms in metal hydrides to yielddeutero- and/or tritiato-metal compounds. Substitution of the hydrogenatoms by deuterium and/or tritium enables the stabilization of someunstable hydrides, including all antimony trihydrides (e.g., stibine,SbH₃) or substituted dihydrides of antimony.

This stabilization improvement is attributable to the hydrogen isotopeeffect. This effect involves lowering of the ground electronic state(zero point energy) of the deuterium and/or tritium analog compared tothe non-deuterated compound. By lowering the ground state, thedeuterated and/or tritiated compound is much more stable, i.e., lessreactive, than its proteo analog. The theoretical value of k_(H) /k_(D)is approximately 6.5 for reactions involving C--H bonds. When hydrogenatoms are attached to the heavier elements such as transition metals,this value is frequently much greater than 6.5. Such increase of k_(H)/k_(D) is attributable to the phenomenon of quantum mechanicaltunneling, whereby the height of the activation barrier is effectivelylowered due to the ability of the lighter isotope (in this casehydrogen) to tunnel across the barrier of potential energy surface.

In one aspect, the present invention relates to complexes of the type

    D.sub.x MR.sub.y

where:

each D is independently selected from deuterium (² ₁ H) and tritium (³ ₁H) isotope;

M is a metal selected from the group consisting of Group III, IV or Vmetals and transition metals;

each R is independently selected from C₁ -C₈ alkyl, C₁ -C₈perfluoroalkyl, C₁ -C₈ haloalkyl, C₆ -C₁₀ aryl, C₆ -C₁₀ perfluoroaryl,C₆ -C₁₀ haloaryl, C₆ -C₁₀ cycloalkyl, substituted C₆ -C₁₀ aryl and halo;and

x and y are each independently from 0 to 6 inclusive.

When R is substituted C₆ -C₁₀ aryl, the substituents may beindependently selected, inter alia, from C₁ -C₈ alkyl, C₁ -C₈ haloalkyl,and halo.

In instances where the cost is not a factor, such as in ion implantapplications, tritium may be used instead of deuterium to realize evengreater stability than is achievable by the deuterium substitution ofthe complex.

Another aspect of the invention relates to a metal hydride derivativewherein at least one hydrogen atom is replaced by deuterium (² ₁ H) ortritium (³ ₁ H) isotope. The metal hydride's metal constituent isselected from Group III, IV and V metals and transition metals and mayfor example comprise antimony, aluminum, gallium, tin, germanium, orindium.

The metal hydride of the invention may have the formula MY_(n)

wherein M is an n-valent metal,

each Y is independently selected from hydrogen, deuterium (² ₁ H)isotope, atritium (³ ₁ H) isotope, and halo,

n is at least 2,

with the proviso that at least one Y constituent is either deuterium (21H) isotope or tritium (³ ₁ H).

In such metal hydride, n may be from two to six, inclusive.

Another aspect of the invention relates to metal hydride derivatives ofthe formula:

    D.sub.x MR.sub.y

wherein:

M is a z-valent metal selected from Group III, IV and V metals andtransition metals;

each D is independently selected from hydrogen, deuterium (² ₁ H)isotope and tritium (³ ₁ H) isotope;

each R is independently selected from alkyl, C₁ -C₈ alkyl, C₁ -C₈perfluoroalkyl, C₁ -C₈ haloalkyl, C₆ -C₁₀ aryl, C₆ -C₁₀ perfluoroaryl,C₆ -C₁₀ haloaryl, C₆ -C₁₀ cycloalkyl, substituted C₆ -C₁₀ aryl and halo;

x is at least one;

x+y z;

with the proviso at least one D is either deuterium (² ₁ H) isotope ortritium (³ ₁ H) isotope.

The invention in a further aspect relates to deuterated stibine, Sb(² ₁H)₃, deuterated deuterated tin, Sn(² ₁ H)₄, deuterated gallium, Ga(² ₁H)₃, deuterated germanium, Ge(² ₁ H)₄, and deuterated aluminum, Al(² ₁H)₃ or Al(² ₁ H)₃ •L, where L is a Lewis base. Such Lewis base may be ofany suitable species, e.g., glymes, tetraglymes, polyamines, etc.

The metal deuterides and tritiides of the invention have utility asprecursors for ion implantation, as well as for chemical vapordeposition (CVD), or beam-induced CVD (e.g., laser, light, plasma, ion,etc.).

In yet another aspect of the invention, there is provided a non-aqueousmethod of making a metal hydride derivative at least one of whosehydrogen atoms is replaced by a deuterium (² ₁ H) isotope or a tritium(³ ₁ H) isotope, comprising reacting a metal halide compound whose metalmoiety is the same metal as the metal of the metal hydride product, witha metal hydride reactant of the formula:

    M.sub.1 M.sub.2 D.sub.a

wherein M₁ is selected from the group consisting of lithium, sodium andpotassium;

M₂ is selected from the group consisting of aluminum, gallium and boron;and

each D is independently selected from the group consisting of hydrogen,deuterium (² ₁ H) isotope and tritium (³ ₁ H) isotope, with the provisothat at least one D is deuterium or tritium isotope.

The above-described reaction of the metal halide compound and metalhydride reactant is advantageously carried out in a reaction volumeincluding a solvent such as etheric solvents, glycols and/or polyamines.

In another aspect, the invention relates to a method of depositing ametal M from a metal-containing precursor therefor, comprising using asa precursor a metal hydride derivative wherein at least one hydrogenatom is replaced by deuterium (² ₁ H) isotope or tritium (³ ₁ H)isotope.

In such method, the metal may be deposited by a process selected fromthe group consisting of chemical vapor deposition, assisted chemicalvapor deposition (e.g., laser, light, plasma, ion, etc.), ionimplantation, molecular beam epitaxy, and rapid thermal processing.

Still another aspect of the invention relates to a storage anddispensing system for a metal hydride gas, comprising:

a vessel containing (1) a sorbent material having sorptive affinity forthe metal hydride gas and (2) metal hydride gas;

wherein the metal hydride gas comprises a metal hydride derivativewherein at least one hydrogen atom is replaced by deuterium (² ₁ H) ortritium (³ ₁ H) isotope.

In such storage and dispensing system, the sorbent material may suitablycomprise a solid physisorbent material. Alternatively, the sorbentmaterial may comprise a liquid sorbent in which the metal hydride gas issoluble, such as polyethers, glycols, cryptanes and crown ethers.

Other aspects, features and advantages of the present invention will bemore fully apparent from the ensuing disclosure and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a spectrum of SbH3/impurity gas mixture immediately aftersynthesis and isolation, in which the Sb-H stretch at 1885 cm-1 isclearly visible as the strongest absorption in the spectrum.

FIG. 2 shows a spectrum of stibine and a synthetic impurity after 1 dayof storage at room temperature, in which the relative intensity of theSb-H stretch (1890 cm⁻¹) as compared to the impurity stretch observed at˜2300 cm-1 reveals that there is less stibine present in the gasmixture.

FIG. 3 shows an FTIR spectrum of volatiles in a storage container aftercomplete decomposition of stibine into H₂ and Sb (m), as evidenced bythe complete disappearance of the Sb-H stretch at 1890 cm⁻¹.

FIG. 4 shows a gas phase FTIR of SbD₃ immediately after synthesis, inwhich the Sb-D stretch, located at 1362 cm-1 is shifted nearly 530 cm-1from the Sb-H stretch observed in stibine.

FIG. 5 shows a gas phase FTIR spectrum of volatile components in a SbD₃storage container after 3 days of storage at room temperature.

FIG. 6 shows a gas phase FTIR spectrum of volatiles in a SbD₃ containerafter 6 days storage at room temperature, with the SbD₃ exhibiting nodecomposition at 10 Torr.

FIG. 7 is a schematic representation of a gas storage and dispensingvessel holding a sorbent medium and a deuterated and/or tritiatedsorbate gas according to the invention.

DETAILED DESCRIPTION OF THE INVENTION, AND PREFERRED EMBODIMENTS THEREOF

The present invention is based on the discovery that metal hydridespecies which are inherently unstable at ambient temperature conditionscan be stabilized via deuteration and/or tritiation thereof.

An illustrative example is stibine trideuteride, SbD3, which in itsfully hydridic form, SbH3, is unstable and therefore unavailable as aprecursor material for antimony at room temperature in uses such as ionimplantation, chemical vapor deposition, etc.

SbD3 offers the possiblity of being the ultimate antimony source for ionimplantation and chemical vapor deposition (CVD) and beam-inducedapplications due to its volatility and its lack of potential contaminantelements.

Such SbD3 antimony source may be provided in a preferred form as asorbate which is sorptively retained on a suitable sorbent medium in astorage and dispensing vessel holding the physical sorbent and the SbD3antimony source material, in accordance with the disclosure of U.S. Pat.No. 5,518,528 issued May 21, 1996 in the names of Glenn M. Tom and JamesV. McManus. The storage and dispensing vessel is equipped with suitabledispensing means such as a conventional valve head assembly, to provideon-demand dispensing of the storage antimony source gas. Such storageapproach enables a new and valuable antimony source forcommercialization. SbH3 is too thermally unstable to serve as such asource, with thermal decomposition into antimony (metal) and hydrogengas being observed during room temperature storage.

While the invention is discussed herein primarily in terms of stibinetrideuteride, it will be recognized that the utility of the invention isnot thus limited, but rather extends to and encompasses other metalswhich are amenable to deuteration or tritiation. Examples include GroupIII, IV and V metals and transition metals. Because the presentinvention facilitates a long-sought antimony source material, thefollowing discussion will be directed primarily to deuterides andtritiates of such metal, it being recognized that the invention isbroadly applicable to a wide variety of other metals having stable aswell as unstable hydride forms. Even where the metal hydride per se isstable, e.g., at ambient temperature and pressure conditions, it may bedesirable to utilize the deuterated and/or tritiated forms of suchcompounds, to realize even higher stability, as may be advantageous forexample for storage and transport of such derivatives of other metals.

SbD₃ has superior stability relative to SbH₃, and at sufficiently lowstorage pressures, no detectable decomposition of the molecule occurs(e.g., during room temperature storage for six days). By contrast, SbH₃which was stored in a hexamethyldisilazane-passivated glass containerbegan to show signs of decomposition after storage for two days at roomtemperature and was completely decomposed by the third day.

The synthesis of stibine and deutero-stibine may be effected via a novelreaction route which employs a non-aqueous reaction medium and commonreducing agents, by the illustrative non-aqueous reactions shown inequations 1-4 below: ##STR1## Yields approaching 70% are readilyobtainable in these reactions. The materials which were collected tendto be much purer for the LiAlH₄ and LiAlD₄ reactions, due to theformation of borohydrides and borodeuterides in the reactions describedin equations 2 and 4. These borohydrides and borodeuterides can easilybe separated from the stibine(s) (2) and the deuterated Sb compound (4).

Illustrative data showing the stability of SbD₃ relative to SbH₃ wereobtained, and are discussed below.

Gas phase FTIR spectra were generated for SbH₃ which was stored atapproximately 10 Torr vapor pressure in a glass container which had beensurface passivated using 1,1,1-3,3,3-hexamethyldisilizane. FIG. 1 is thespectrum of the volatiles collected immediately after the reaction. Itreveals the presence of SbH₃, with strong Sb-H stretching centered at1885 cm-1 (a volatile impurity is observed with stretching at ˜2300cm⁻¹). This spectrum serves as the baseline for comparison of the FTIRspectra shown in FIGS. 2 and 3.

FIG. 4 is the spectrum for the volatiles in the container, afterdegassing at -196° C., after one day of storage at room temperature. Ofnote in the spectrum is the decrease in the relative intensity of theSb-H stretch (1885) when compared to the stretch observed at ˜2300 cm-1.This decrease in intensity indicates that SbH₃ begins to decomposeduring 24 hours of storage at room temperature. Even this limitedstability is still an improvement over stibine, which when stored inuntreated glassware, exhibits signs of decomposition immediately uponwarming to room temperature.

FIG. 3 shows the volatile components left in the storage container afterdegassing at -196° C. Clearly, all of the stibine has decomposed by thispoint (˜3 days at room temperature), as there is no longer Sb-Hstretching visible at 1885 cm-1.

A second set of gas phase FTIR spectra was obtained for the volatilecomponents of a completely untreated glass container used to store SbD₃.The gas was stored at ˜10 Torr pressure at room temperature for six dayswith no noticeable signs of decomposition. In each case, the onlyobservable species corresponds to SbD₃ (with Sb-D stretching observed at1362 cm-1) and a very small quantity of SbH₃ (present from the fact thatdeuterated reagents are typically not 100% deuterated, but also containa small fraction of H) as evidenced by the stretch at 1885 cm-1.

The three spectra displayed in FIGS. 4, 5, and 6 correspond to thevolatile components of the container (i) after the synthesis of themolecule, (ii) after three days of storage at room temperature and (iii)after six days of storage at room temperature, respectively. In eachcase, the SbD₃ remains unchanged and shows no decrease in intensity (nordid the total pressure of the SbD₃ change observably over this timeperiod).

FIG. 4 shows the gas phase FTIR spectra of SbD₃ immediately aftersynthesis. The Sb-D stretch, located at 1355 cm-1 is shifted nearly 530cm-1 from the Sb-H stretch observed in stibine.

FIG. 5 shows the gas phase FTIR spectrum of volatile components in theSbD₃ storage container after 3 days of storage at room temperature.

FIG. 6 shows the gas phase FTIR spectrum of volatiles in SbD₃ containerafter 6 days storage at room temperature. The SbD₃ exhibits nodecomposition at 10 Torr.

Based on these results it is readily apparent that deuterated stibine isfar more stable than its hydride analog. The efficiency of SbD₃ as asuitable antimony source for ion implantation and chemical vapordeposition, having superior stability to stibine per se, isdemonstrated.

The foregoing illustrates that antimony trihydride (stibine), SbH₃, andantimony trideuteride, SbD₃, may be synthesized in high yields via thenon-aqueous synthetic route of the present invention. The results alsoillustrate that deuterated stibine displays significantly greaterthermal stability than its hydride analog via isotopic stabilization andcan be stored for weeks at room temperature with minimal decomposition.

Thermal decomposition of SbD₃ was performed at 300° C. in a horizontal,hot-wall CVD reactor. Decomposition efficiencies approaching 50% wereachieved when SbD₃ was diluted with H₂ co-reactant. As this researchdemonstrates, deuterated stibine is an ideal CVD source due to itsgaseous state, compositional simplicity and lack of Sb-C bonds, and itsability to deposit high-purity Sb films at relatively low temperatures.

SbD₃ thus provides a precursor molecule that offers carbon-freedecomposition at substrate temperatures below 200° C., exhibitingenhanced thermal stability at room temperature relative to its hydrideanalog and being storable for prolonged periods of time with minimaldecomposition.

SbH₃ may be synthesized in high yield via reaction of antimony(III)chloride and lithium aluminum hydride in tetraethylene glycol dimethylether ("tetraglyme") solvent at -30° C., as depicted in Equation 1.Other reductants, such as NaBH4 and LiH, can also employed for thesynthesis of stibine, but LiAlH4 was found to give the highest yields.

The stibine generated from this reaction may be trapped in a cold trapkept at -130 ° C. The use of a high boiling, coordinating solvent, suchas tetraglyme (Tb=275° C.), is particularly useful in separating stibinefrom the reaction mixture.

Deuterated stibine, SbD₃ may be readily synthesized by the syntheticprocedure described above, after replacing LiAlH4 with LiAlD4. Again,the use of other deuterated reducing agents such as NaBD4 and LiDresults in lower yields of SbD₃.

The most striking feature of the IR spectrum for SbD3 is its similarityto that of SbH3 in terms of the observed stretching and bending modes.Importantly, however, the energies at which these vibrational modesoccur are greatly shifted with respect to those observed in SbH₃. Theobserved energy of the Sb-D stretch is 1362 cm-1. This corresponds to anisotopic shift (Δν) of nearly 500 cm-1 compared to the Sb-H stretching.The bending modes are observed to shift to lower relative energies whencompared to those observed in SbH₃. In accordance with Hooke's Law, thisspectral shift is due to the reduced mass difference in Sb-D relative toSb-H.

Quantum mechanical tunneling provides a facile mechanism for thedecomposition of many unstable metal hydrides. Deuterium, because of itsincreased mass, is unable to readily tunnel through the quantum"tunnel". This behavior of "quantum mechanical tunneling" phenomena,whereby the height of the activation energy barrier is effectivelyincreased due to the inability of the heavier isotope (in this casedeuterium) to tunnel through the barrier is exploited in accordance withthe present invention to stablize stibine and other metal hydrides.

FIG. 7 is a schematic representation of a gas storage and dispensingvessel 10 holding a sorbent medium 12 and a deuterated and/or tritiatedsorbate gas according to the invention. The gas storage and dispensingvessel may be constructed and arranged as more fully described in theaforementioned Tom et al. patent, and features a dispensing manifold 14joined to the valve head 16 of the vessel as illustrated. By theapparatus shown in FIG. 7, the deuterated and/or tritiated metal sourcereagents of the present invention may be stored for extended periods oftime, and supplied on demand for such applications as ion implantationand chemical vapor deposition.

The features and advantages of the invention are more fully shown by thefollowing non-limiting Examples, in which the symbol D in chemicalformulae denotes deuterium isotope.

In these Examples the experimental procedures were as follows:

General Procedures: All synthetic work was performed in a nitrogenfilled glovebox or under dry nitrogen using standard vacuum-line andSchlenk techniques. Unless noted otherwise, all chemicals were used asreceived from the vendor. The FTIR spectra were collected on a PerkinElmer model 1650 spectrometer. Nuclear magnetic resonance spectra wererecorded on a Varian Gemini 200 MHz spectrometer.

Thin Film Deposition: The thin films described below were deposited in ahorizontal, resistively heated, hot-walled CVD reactor. Temperaturecontrol was accomplished using a temperature controller and bothreactant and carrier gases were introduced via mass flow controllers.Pumping of the reactor system is accomplished using a liquid nitrogentrapped diffusion pump and provides a base pressure 7×10⁻⁵ Torr.Processing pressures were monitored via a capacitance manometer (MKSModel) and varied by changing the reactant and carrier gas flow rates.The condensible volatiles of the reactions were collected in a glasstrap cooled to -196° C. by liquid nitrogen and were analyzed using FTIRor, when possible, NMR. Analysis of these byproducts in conjunction withanalysis of the film properties and compositions allowed foroptimization of the processing conditions.

Film Composition. The composition and morphology of the films depositedwas investigated using x-ray diffraction (XRD), energy dispersive x-rayanalysis (EDS), scanning electron microscopy (SEM) and atomic forcemicroscopy (AFM).

I. Synthesis of SbH₃ (1): Stibine was synthesized via an aqueousreaction route and via two novel nonaqueous reaction routes.

Method A: A 500 ml flask was charged with a solution of 12 mlcon-centrated sulfuric acid in 100 ml distilled, de-ionized water andcooled to 0° C. A 50 ml aqueous solution of KOH (6 g, 107 mmol), SbCl₃(0.5 g, 2.2 mmol) and NaBH₄ (0.42 g, 11 mmol) was prepared by dissolvingthe reagents, in the order in which they are listed, in 50 ml distilledde-ionized water. The latter solution was then added dropwise, withcontinuous stirring, to the former over a period of fifteen minutes.During this time, the reaction flask was open to a high vacuum manifoldbackfilled with 760 Torr of dry nitrogen. The mixture immediately turneda light brown color, which darkened to black very rapidly withcontinuing addition of the reagents. After approximately one-half of theantimony solution had been added, the reaction flask was opened tovacuum and the volatiles were passed through traps held at -78° C.,-130° C. and -196° C., respectively. The -130° C. trap was found tocontain SbH₃ (0.12 g, 0.96 mmol, 44%).

Method B: A 500 ml flask was charged with a suspension of NaBaH₄ (0.43g, 11 mmol) in 100 ml tetraglyme and cooled to 0° C. A solution of SbCl₃(0.5 g, 2.2 mmol) in 50 ml tetraglyme was prepared in a nitrogen-filledglove box and then placed in an addition funnel. The reaction flask andthe addition funnel were then connected using standard Schlencktechniques. These were then degassed by opening them to vacuum. Thereaction was begun by slowly adding the antimony solution to the cooled,stirred sodium borohydride suspension. The suspension was observed toturn black with continuing addition of the antimony solution, and theevolution of a gas from the surface of the tetraglyme was readilyevidenced by bubbling. The volatiles produced during the reaction werecontinuously passed through traps held at -20° C. and -130° C. and -196°C. The -130° C. trap was found to contain stibine (0.17 g, 1.4 mmol,62%). The -20° C. trap was employed to condense any tetraglyme, but atthe reaction temperature of 0° C., none was observed. The -196° C. trapwas found to contain a very volatile species which is believed to be aBH_(x) containing byproduct of the reaction.

Method C: A 500 ml flask was charged with a suspension of purifiedLiAlH₄ (0.51 g, 13 mmol) in 100 ml tetraglyme and cooled to -30° C. Asolution of SbCI3 (0.5 g, 2.2 mmol) in 50 ml tetraglyme was prepared ina nitrogen-filled glove box and then placed in an addition funnel. Thereaction flask and the addition funnel were then connected usingstandard Schlenck techniques and then degassed. The reaction was begunby slowly adding the antimony solution to the cooled, stirred lithiumaluminum hydride suspension. The suspension was observed to turn blackwith continuing addition of the antimony solution, and the evolution ofa gas from the surface of the tetraglyme was readily evidenced bybubbling. The volatiles produced during the reaction were continuouslypassed through traps held at -20° C. and -196° C. The -196° C. trap wasfound to contain stibine (0.19 g, 1.7 mmol, 77%). The -20° C. trap wasemployed to condense any tetraglyme, but at the reaction temperature of-30° C., none was observed.

Vapor Phase FTIR: centered about 1939 cm-1 (m), 1891 cm-1 (vs), centeredabout 1846 cm-1 (m), 1154 cm-1 (vw), 840 cm-1 (w,sh), 820 cm-1 (m), 782cm-1 (m).

II. Synthesis of SbD₃ (2): Deuterated stibine was synthesized in afashion similar to that used in the synthesis of stibine by employingdeuterated reducing agents.

Method A: A 500 ml flask was charged with a suspension of NaBaD₄ (0.50g, 12 mmol) in 100 ml tetraglyme and cooled to -30° C. A solution ofSbCI₃ (0.52 g, 2.3 mmol) in 50 ml tetraglyme was prepared in anitrogen-filled glove box and then placed in an addition funnel. Thereaction was conducted in a fashion identical to that described inmethod B above. The volatiles produced during the reaction werecontinuously passed through traps held at -20° C. and -130° C. and -196°C. The -130° C. trap was found to contain deuterated stibine (0.19 g,1.5 mmol, 65%). The -20° C. trap was employed to condense anytetraglyme, but at the reaction temperature of -30° C., none wasobserved.

The -196° C. trap was found to contain a very volatile species which isbelieved to be a BD_(x) containing byproduct of the reaction.

Method B: A 500 ml flask was charged with a suspension of purifiedLiAlD₄ (0.46 g, II mmol) in 100 ml tetraglyme and cooled to -30° C. Asolu-tion of SbCl3 (0.49 g, 2.2 mmol) in 50 ml tetraglyme was preparedin a nitrogen-filled glove box and then placed in an addition funnel.The addition and workup of this reaction were conducted in a fashionidentical to that described above for method C, except that thevolatiles produced during the reaction were continuously passed throughtraps held at -20° C. and -196° C. only. The -196° C. trap was found tocontain stibine (0.19 g, 1.7 nmol, 77%). The -20° C. trap was employedto condense any tetraglyme, but at the reaction temperature of -30° C.,none was observed.

Vapor Phase FTIR: 2721 cm-1 (vw), 2683 cm-1 (w), 2647 cm-1 (vw),centered about 1399 cm-1 (s), 1356 cm-1 (vs), centered about 1320 cm-1(s), 1138 cm-1 (w), 602 cm-1 (m,sh), 590 cm-1 (s), 557 cm-1 (s).

EXAMPLE I

The thermal stability of SbD₃ was compared to that of SbH₃ by storingequivalent amounts of the respective gases in glass containers ofidentical volume. In a kinetic study that used a 10 Torr total pressureof both SbH₃ and SbD₃ in 250 ml glass storage flasks, the improvedstability of SbD₃ over SbH₃ at room temperature was clearlydemonstrated. The total pressure of SbH₃ increased as a function oftime, while SbD₃ in the identical container exhibited no change as afunction of time. After three days of storage at 10 Torr, all of theSbH₃ decomposed, as confirmed by the visual observation of antimonymetal deposits, the presence of a non-condensable gas at -196° C. (i.e.,H₂) and the absence of Sb-H stretching in the vapor phase FTIR. Whenexamining SbD₃, no change was observed in the total pressure as measuredby a capacitance manometer. In fact, it was not possible to observe anydecomposition in the SbD₃ experiment even after one week at roomtemperature (23° C.). Studies conducted in glass under similarconditions indicate that the critical pressure for the decomposition ofSbD₃ lies between 10 and 20 Torr (250 ml volume). Slow, but continuous,decomposition was observed over a period of days for SbH₃ pressuresabove 20 Torr. Rapid and complete decomposition was observed for storagepressures of 300 Torr or greater.

At first, the low critical storage pressure of SbD₃ at room temperaturewould appear to present a problem for the storage of large quantities ofthis precursor. However, by holding the SbD₃ in a storage and dispensingvessel containing a sorbent material having sorptive affinity for theSbD₃, consistent with the teachings of U.S. Pat. No. 5,518,528 issuedMay 21, 1996 in the names of Glenn M. Tom and James V. McManus, it hasproven possible to store SbD₃ with weight loadings in excess of 30weight percent.

Under these storage vessel conditions, multiple gram quantities of SbD₃have been stored at room temperature (23° C.) for periods of up to twoweeks with little decomposition. Furthermore, after room temperaturestorage for two weeks, it was possible to recover >70% of the originallyadsorbed SbD₃. The improved thermal stability of SbD₃ and adsorbantstorage methodology make SbD₃ a viable and attractive precursor for thelow temperature CVD of antimonide thin-films.

EXAMPLE II

SbD₃ was thermally decomposed in a horizontal, hot-walled, low pressureCVD reactor. The precursor was introduced both neat and in dilutedmixtures with H2 to yield thin-films of antimony at temperatures as lowas 200° C. Typical deposition run times were fifteen minutes to one hourand resulted in thick films of pure antimony. Films were deposited ontoglass (pyrex), quartz, Si and Pt overcoated silicon wafers. Goodadhesion was observed on Pt/Si and glass, but the films were easilyremoved from Si and SiO₂ substrates. Films of several microns thicknesswere observed to readily delaminate from all substrates, except forPt/Si. The excellent adhesion observed for Pt/Si substrates may resultof the formation of alloys of platinum with antimony. In fact, XRDanalysis of the samples on Pt/Si revealed the presence of Geversite Pt,PtSb₂ Sb₂. No impurities were noted from this or electron diffractionspectroscopic (EDS) analysis.

Utilizing a -196° C. cold trap, attempts to trap decompositionbyproducts revealed the presence of a non-condensable gas (presumablyD₂) and unreacted SbD₃. The amount of SbD₃ consumed during CVD at 300°C. was estimated by recovering unreacted SbD₃ from a 1:40 mixture ofSbD₃ in H₂. Analysis indicates that SbD₃ conversion approached 50%efficiency under these reactor conditions. This decomposition efficiencyis extraordinarily high and clearly demonstrates the utility of SbD₃ forthe low temperature, low-cost deposition of antimonide thin-films.

While the invention has been illustratively described herein withreference to specific features, aspects and embodiments, it will beappreciated that the invention is not thus limited, but rather extendsto and encompasses numerous variations, modifications and otherembodiments. The invention therefore is to be correspondingly broadlyconstrued consistent with the claims hereinafter set forth.

What is claimed is:
 1. A metal hydride derivative wherein at least onehydrogen atom is replaced by deuterium (² ₁ H) or tritium (³ ₁ H)isotope, wherein the metal of said metal hydride derivative is selectedfrom the group consisting of: Sc, Y, Ti, Zr, V, Nb, Hf, Ta, Al, Ga, Ge,In, Sb, Tl, Pb, Bi, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Tc, Ru, Rh, Pd, Ag,Cd, W, Re, Os, Ir, Pt, Au, and Hg, subject to the provisos that: whenthe metal is Sb, said metal hydride derivative is selected from thegroup consisting of (i) Sb(³ ₁ H)₃, (ii) SbH(³ ₁ H)₂, and (iii) SbH₂ (³₁ H); and when the metal is Ge, said metal hydride derivative isselected from the group consisting of (i) GeH₂ (² ₁ H)₂, (ii) GeH₃ (² ₁H), (iii) Ge(³ ₁ H)₄, (iv) GeH(³ ₁ H)₃, (v) GeH₂ (³ ₁ H)₂ and (vi) GeH₃(³ ₁ H).
 2. A metal hydride derivative according to claim 1, including ametal constituent selected from the group consisting of antimony,aluminum, indium, gallium, and germanium.
 3. A metal hydride derivativeaccording to claim 1, wherein the metal of said metal hydride derivativeis Sb.
 4. A metal hydride derivative of the formula MY_(n) wherein M isan n-valent metal selected from-the group consisting of: Sc, Y, Ti, Zr,V, Nb, Hf, Ta, Al, Ga, Ge, In, Sb, Tl, Pb, Bi, Cr, Mn, Fe, Co, Ni, Cu,Zn, Mo, Tc, Ru, Rh, Pd, Ag, Cd, W, Re, Os, Ir, Pt, Au, and Hg, each Y isindependently selected from the group consisting of hydrogen, deuterium(² ₁ H) isotope, tritium (³ ₁ H) isotope, and halo, n is at least 2,with the provisos that: at least one Y constituent is either deuterium(² ₁ H) isotope or tritium (³ ₁ H) isotope; when the metal is Sb, saidmetal hydride derivative is selected from the group consisting of (i)SbH₂ (² ₁ H), (ii) SbH(² ₁ H)₂, (iii) Sb(³ ₁ H)₃, (iv) SbH(³ ₁ H)₂, and(v) SbH₂ (³ ₁ H); and when the metal is Ge, said metal hydridederivative is selected from the group consisting of (i) GeH₂ (² ₁ H)₂,(ii) GeH₃ (² ₁ H), (iii) Ge(³ ₁ H)₄, (iv) GeH(³ ₁ H)₃, (v) GeH₂ (³ ₁ H)₂and (vi) GeH₃ (³ ₁ H).
 5. A metal hydride derivative according to claim4, wherein n is from two to six, inclusive.
 6. A metal hydridederivative of the formula:

    Y.sub.x MR.sub.y

wherein: M is a z-valent metal selected from the group consisting of:Sc, Y, Ti, Zr, V, Nb, Hf, Ta, Al, Ga, Ge, In, Sb, Sn, Tl, Pb, Bi, Cr,Mn, Fe, Co, Ni, Cu, Zn, Mo, Tc, Ru, Rh, Pd, Ag, Cd, W, Re, Os, Ir, Pt,Au, and Hg; each Y is independently selected from the group consistingof hydrogen, deuterium (² ₁ H) isotope and tritium (³ ₁ H) isotope; R isindependently selected from the group consisting of C₁ -C₈ alkyl, C₁ -C₈perfluoroalkyl, C₁ -C₈ haloalkyl, C₆ -C₁₀ aryl, C₆ -C₁₀ perfluoroaryl,C₆ -C₁₀ haloaryl, C₆ -C₁₀ cycloalkyl, substituted C₆ -C₁₀ aryl and halo;x is at least one; x+y=z; with the provisos that: at least one Y iseither deuterium (² ₁ H) isotope or tritium (3₁ H) isotope; when y iszero and the metal is Sb, said metal hydride derivative is selected fromthe group consisting of (i) Sb(³ ₁ H)₃, (ii) SbH(³ ₁ H)₂, and (iii) SbH₂(³ ₁ H); when y is 1 or 2, and the metal is Sb, R is not C₁ -C₈ alkyl;when y is zero and the metal is Ge, said metal hydride derivative isselected from the group consisting of (i) GeH₂ (² ₁ H)₂, (ii) GeH₃ (² ₁H), (iii) Ge(³ ₁ H)₄, (iv) GeH(³ ₁ H)₃, (v) GeH₂ (³ ₁ H)₂ and (vi) GeH₃(³ ₁ H); and when the metal is Sn, y is at least one.
 7. A metal hydridederivative according to claim 6, wherein at least one Y is deuterium (²₁ H) isotope.
 8. A metal hydride derivative according to claim 6,containing at least two deuterium (² ₁ H) isotope constituents.
 9. Ametal hydride derivative according to claim 6, wherein M is Sb, Al orIn.
 10. A metal hydride derivative of the formula:

    Y.sub.x MR.sub.y

wherein: M is a z-valent metal selected from the group consisting of:Sc, Y, Ti, Zr, V, Nb, Hf, Ta, Al, Ga, Ge, In, Sb, Sn, Tl, Pb, Bi, Cr,Mn, Fe, Co, Ni, Cu, Zn, Mo, Tc, Ru, Rh, Pd, Ag, Cd, W, Re, Os, Ir, Pt,Au, and Hg; each Y is independently selected from the group consistingof hydrogen, deuterium (² ₁ H) isotope and tritium (³ ₁ H) isotope; R isindependently selected from the group consisting of C₁ -C₈ alkyl, C₁ -C₈perfluoroalkyl, C₁ -C₈ haloalkyl, C₆ -C₁₀ aryl, C₆ -C₁₀ perfluoroaryl,C₆ -C₁₀ haloaryl, C₆ -C₁₀ cycloalkyl, substituted C₆ -C₁₀ aryl and halo;x is at least one; x+y=z;wherein at least one Y is tritium (³ ₁ H)isotope.
 11. A deuterated composition selected from the group consistingof deuterated gallium, Ga(² ₁ H)₃, deuterated indium, In(² ₁ H)₃ or In(²₁ H)₃ •L, and deuterated aluminum, Al(² ₁ H)₃ or Al(² ₁ H)₃ •L, whereinL is a Lewis base.
 12. A deuterated composition according to claim 11,wherein the Lewis base is selected from the group consisting of glymes,tetraglymes, and polyamines.
 13. A metal hydride derivative compoundwherein at least one hydrogen atom is replaced by tritium (³ ₁ H).
 14. Ametal hydride derivative compound according to claim 13, wherein themetal of said metal hydride derivative compound is selected from thegroup consisting of: Sc, Y, Ti, Zr, V, Nb, Hf, Ta, Al, Ga, Ge, In, Sb,Sn, Tl, Pb, Bi, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Tc, Ru, Rh, Pd, Ag, Cd,W, Re, Os, Ir, Pt, Au, and Hg.
 15. An antimony hydride derivative of theformula:

    Y.sub.x SbR.sub.y

wherein: each Y is independently selected from the group consisting ofhydrogen, deuterium (² ₁ H) isotope and tritium (³ ₁ H) isotope; R isindependently selected from the group consisting of C₁ -C₈ alkyl, C₁ -C₈perfluoroalkyl, C₁ -C₈ haloalkyl, C₆ -C₁₀ aryl, C₆ -C₁₀ perfluoroaryl,C₆ -C₁₀ haloaryl, C₆ -C₁₀ cycloalkyl, substituted C₆ -C₁₀ aryl and halo;x is at least one; y is at least one; x+y=3; with the proviso at leastone Y is tritium (³ ₁ H) isotope.